Posted
by
timothyon Wednesday October 07, 2009 @04:43PM
from the elephant-detector-working-fine dept.

coondoggie writes "NASA scientists have recalculated the path of a large asteroid known as Apophis and now say it has only a very slim chance of banging into Earth.. The Apophis asteroid is approximately the size of two-and-a-half football fields, and updated computational techniques and newly available data indicate the probability of an Earth encounter on April 13, 2036 for Apophis has dropped from one-in-45,000 to about four-in-a million, NASA stated."

This is like those COPS shows, where they are following a high speed chase from a helecopter. The announcer is always announcing how they nearly hit the pedestrians, who were on the sidewalk, on the opposite side of the street.

I am a programmer. I am paid to produce syntax not grammar. Deal with it.

Sorry for the off-topic troll, but I really can't resist your signature. I'll answer your self-satisfied, pedantic quibble with one of my own.

Programmers, unless they are creating new languages, do not produce syntax, they obeysyntax [wikipedia.org]. Setting this point aside, maybe you meant, "I am paid to produce things which are syntactically correct, not things which are grammatically correct." Of course, you actually are paid to produce things that are grammatically [wikipedia.org] correct.

Perhaps you meant, "I am paid to write in the highly precise, fascinating languages of computers and not the boring, ambiguous English language that my incompetent high school teachers made me hate." That might be true, but it probably isn't. Most programming jobs require quite a bit of written English, and the more grammatically correct it is, the better. Admittedly, this is usually less important than producing working code.

Another possible reading: "I never quite understood English grammar, even though I felt like I should. I compensate by basing my fragile self image on excessive pride in my other skills and wearing a chip on my shoulder so people will be afraid to call me on it."

How about 1 in 250,000? And "two football fields" doesn't tell us much about the thing's actual size.

You're translating from Jock to Geek. The Jock's understand a million as "a really big number" and 4 as a really small one. 250 is compleltely beyond them, let alone 250 times 1000! Football fields is a much more natural unit to them than a meter. Never mind that they're different sizes - they can all relate to being exhausted running the length of a football field. The concept of a meter just hurts their poor roid ridden brains.

Yeah, I RTA, saw the image of an asteroid that was apparently about 60km long, with the text "The Apophis asteroid is approximately the size of two-and-a-half football fields" and I suddenly had a whole lot more respect for US football.

Apophis had been downgraded to 4 chances in a million from 22 chances in a million. This new figure is clearly wrong, because it has 6 chances to impact between 2036 and 2103 (see http://neo.jpl.nasa.gov/risk/a99942.html [nasa.gov] ). Perhaps this means the actual metric is 6 chances per 1.5 million.

Also of note in the upgraded data is the second of the 2068 near misses, having a 0.00 Earth radius distance. This is likely a statistical artifact caused by the fact that a near miss is a hit (a miss is a miss or it isn't; something that comes close but doesn't hit is a near hit).

Since the distance is zero but the impact probability is 1.1e-07, they have almost certainly determined that it will pass by (and/or impact) almost perfectly edge on. Due to its size being equivalent to 2.5 football fields, and a football field being a 2 dimensional rectangle with no thickness, an edge on impact would have little effect, keeping all 510 megatons of impact energy confined within an area of 270 by 0.000... meters, ie. no area at all. Thus, the impact will have absolutely no effect unless you happen to be standing over that 270 by zero meter line when it comes down on you, or worse, up at you after having passed through the Earth (a zero thickness should be able to pass through the planet like a neutrino).

Hopefully we will also get updated figures on 2007 VK184. It has a 340 in 1 million chance of impact. It gets 4 attempts between 2048 and 2057. Four chances in 9 years gives it 2.25 million years to have its one million attempts, in which time it will only hit Earth 340 times, or once every 2417095.5882352941176470588235294 days. This was calculated with due attention paid to leap years, though it is uncertain at the time of publication whether the frequent legislating of time standards by the US will result in the figure being in standard leap years or daylight savings leap years.

Just to add a minor point of confusion, in case it has been so far missed: the question has been raised regarding the actual size of these objects, as 'football field' is ambiguous, there being two different kinds of 'football' using different size fields. The answer is that it doesn't matter. NASA has already proven themselves to be above and beyond the need for conversion factors, and so they need not differentiate between metric and non-metric football. In their usual excessively polite manner, Canada has repeatedly not pointed out that they too have 'football' similar to the US kind, but with yet another differently sized field. Their reticence is somewhat practical when one considers that fewer people watch Canadian football than watch curling, and nobody outside Canada watches that.